Marcos Aurélio Lopes

Development and validation of a model to compute the surface area of broiler chickens

Surface area (As) of poultry is an important input parameter in heat and mass transfer calculation; thus, it was aimed with the present work to develop and to validate an empirical model to estimate the broiler chickens surface area. Eighty four Ross broiler chickens were used in this research, thirty seven male and forty seven female, with body masses during all growth phase. In the laboratory, each randomly selected chicken had its dimensions (length, width and height) and body mass evaluated. The chicken skin with feathers was taken off to determine As. Portion of the data was used to fit the equation to estimate the surface area and another portion was used to validate it. Results showed that the empirical equation to determine As was statically significant (P 0.05).

DIGITAL SURFACE AREA ASSESSMENT OF BROILER CHICKENS

Surface area (SA) of poultry is an important parameter for heat and mass transfer calculations. Optical approaches, such as the moire technique (MT), are non-destructive, result in accuracy and speed gains, and preserve the object integrity. The objective of this research was to develop and validate a new protocol for estimating the surface area (SA) of broiler chickens based on the MT. Sixty-six Ross breed broiler chickens (twenty-seven male, thirty-nine female, ages spanning all growth phases) were used in this study. The dimensions (length, width and height) and body mass of randomly selected broiler chickens were evaluated in the laboratory. Chickens were illuminated by a light source, and grids were projected onto the chickens to allow their shape to be determined and recorded. Next, the skin and feathers of the chickens were removed to allow SA to be determined by conventional means. These measurements were then used for calibration and validation. The MT for image analysis was a reliable means of evaluating the three-dimensional shape and SA of broiler chickens. This technique, which is neither invasive nor destructive, is a good alternative to the conventional destructive methods.

RESULTADOS ECONÔMICOS DA ATIVIDADE LEITEIRA NA REGIÃO DE LAVRAS (MG) NOS ANOS 2004 E 2005: UM ESTUDO MULTICASOS

It was studied the profitability of the milk production in 17 properties in the region of Lavras (MG), and the components that had the greatest influence on the final costs of the business were identified. The data were monthly collected from January 2004 to December 2005. The gross margin, net margin, and the result (profit or loss) were taken into consideration as indicators of economic efficiency. The component items of the effective operational cost that had the greatest influence upon the costs of dairy business were, in decreasing order, feeding (55.9%), labor (19.1%), different expenses (11.3%), energy (7.1%), health (4.9%), milking (0.74%), taxes (0.74%), and artificial insemination (0,23%). The net margin and the positive result show the farmers have conditions to produce in middle and long terms, with consequent capitalization. Although, the results of the study can not be extrapolated, since they do not represent a random sampling.

Prediction of physiological responses of Holstein dairy cows

The goal of the present study was to evaluate techniques for modeling the physiological responses, rectal temperature, and respiratory rate of black and white Holstein dairy cows. Data from the literature (792 data points) and obtained experimentally (5.884 data points) were used to fit and validate the models. Each datum included dry bulb air temperature, relative humidity, rectal temperature and respiratory rate. Three models based on artificial intelligence - fuzzy logic, artificial neural networks, and neuro-fuzzy networks - and one based on regression were evaluated for each response variable. The adjusted models predict rectal temperature and respiratory rate as a function of dry-bulb air temperature and relative humidity. The adjusted models were compared using statistical indices. The model based on artificial neural networks showed the best performance, followed by the models based on neuro-fuzzy networks, fuzzy logic, and regression; the last two performed similarly.

Comparativo entre certificadoras de rastreabilidade credenciadas para o SISBOV-MAPA

Com este trabalho avaliou-se o que esta sendo oferecido pelas empresas operadoras de rastreabilidade credenciadas pelo Ministerio da Agricultura, Pecuaria e Abastecimento. A pesquisa foi dividida em duas etapas distintas, a primeira consistiu em avaliar a forma como a empresa se apresenta na Internet, considerando os seguintes quesitos: Tempo de Carga, Aparencia, Estrutura e Navegacao, Usabilidade, Conteudo e Especificas para a Pesquisa. A segunda etapa, consistiu em submeter as duas empresas que obtiveram os melhores desempenhos no Questionario de Avaliacao de Web Site (primeira etapa) a uma avaliacao do Software por elas utilizados para fazer a certificacao. Tal avaliacao verificou se o software e de facil operacao, se os relatorios fornecidos sao claros e eficientes, se a documentacao e suficiente para o usuario, se constam as formas de suporte oferecido ao usuario e se o software permite comunicacao com outros equipamentos.

Custo leite para windows: software de controle de custos para a pecuária leiteira

The objective of this work was to develop a software to assist the technicians and producers in the determination of the cost of production of milk. The Milk Cost is made up of a plan of calculations encompassing both expenses and incomes. The user can put into a spreadsheet all the expenses and incomes concerning to the milk production system. The software enables the spreadsheet of all the estates and facilities of the production system, aiming the calculations of depreciation and remuneration of the capital. The Milk Cost calculates and presents to the user the following variables: total of the incomes, total of the operational costs, total costs, gross margin, net margin, profit, operational cost and total cost per kilogram of milk, break even point of the production system, total amount of milk produced, value of the property, capital remuneration, average yield of the cows (kg/day) and milk yield in kg/ha/month. The system enables the user a number of simulations involving all the parameters and variables, showing the strangulation pointstand helping both the technician and the stockman to determine milk production cost with precision and considerable quickness.

Desenvolvimento de um sistema computacional para dimensionamento e evolução de rebanhos bovinos

The objectives of this study were to develop a software that accomplishes both the dimensioning and evolution of cattle herds and develop a tool which makes it possible for the user to perform simulations with production systems of milk and or beef. The language employed was CA Clipper. The routines have been developed in a conversational form, with an access to the several programs by means of self-explicative menus. The developed system can aid both the technician and the raiser in dimensioning and evolution of a cattle herd with precision and outstanding rapidity; it allows to the user to perform a number of simulations; and it is considered an important tool in the assistance to decision-making.The objectives of this study were to develop a software that accomplishes both the dimensioning and evolution of cattle herds and develop a tool which makes it possible for the user to perform simulations with production systems of milk and or beef. The language employed was CA Clipper. The routines have been developed in a conversational form, with an access to the several programs by means of self-explicative menus. The developed system can aid both the technician and the raiser in dimensioning and evolution of a cattle herd with precision and outstanding rapidity; it allows to the user to perform a number of simulations; and it is considered an important tool in the assistance to decision-making.

Diagnóstico de propriedades em regime de economia familiar e da qualidade do leite no município de Gouveia-MG

Objetivou-se realizar o diagnostico de propriedades produtoras de leite, em regime de economia familiar, no que diz respeito aos aspectos relacionados a qualidade do leite. Foram realizadas entrevistas, em 11 propriedades produtoras de leite do municipio de Gouveia, MG, entre 04 a 30 de julho 2016. As informacoes foram coletadas a partir de um formulario semiestruturado com 97 perguntas. Realizou-se analises de Contagem de Celulas Somaticas (CCS) e Contagem Bacteriana Total (CBT) do leite de todas as propriedades visitadas (uma analise/propriedade), para verificar a sua qualidade microbiologica. Os resultados demonstram que, aproximadamente, 21% dos produtores estariam com valores de CBT nos limites iniciais impostos pela Instrucao Normativa no 62. Com respeito a CCS, 9,1% dos produtores estariam desqualificados, demonstrando que, na regiao estudada, a qualidade microbiologica, sendo considerado como o principal problema relacionado a qualidade do leite. Os principais pontos fortes observados foram: os produtores residem na propriedade, tem mais de seis anos de experiencia na atividade leiteira, a propriedade possui energia eletrica e nascente de agua, armazenam o leite na propriedade no tanque de expansao no maximo por dois dias e existe calendario sanitario. Quanto aos pontos fracos, foram: baixa escolaridade dos produtores, nao procuram capacitacao, nao possuem estrategias para melhora na qualidade do leite e nao e realizado tratamento de agua. A bovinocultura de leite na regiao de Gouveia, MG, se caracteriza por apresentar deficiencias significativas que comprometem a produtividade e a eficiencia na obtencao de leite de qualidade, onde se constata, dentre outras, uma falta de profissionalizacao dos proprietarios e insuficiente oferta de assistencia tecnica.

Rentabilidade do Uso de Tecnologias em Sistema de Produção de Leite com Vacas F1 Holandês x Zebu

Analisou-se, por meio de simulacao, o efeito do uso de tecnologias na rentabilidade da atividade leiteira de um sistema de producao de leite. A referencia zootecnica foi do rebanho composto por vacas F1 Holandes x Gir da Fazenda Experimental de Felixlândia (FEFX) da Empresa de Pesquisa Agropecuaria de Minas Gerais (EPAMIG). O inventario bem como as despesas, as receitas e os demais dados foram cadastrados no software CUSTO BOVINO LEITE 1.0, visando obter a analise de rentabilidade. O uso dos manejos de amansamento de primiparas no pre-parto e o acompanhamento do peso vivo ao parto; o uso do manejo de quatro ordenhas no inicio da lactacao e o uso da qualidade do leite, como diferencial de remuneracao, promoveram um aumento na lucratividade de 8,78%, 4,87% e 16,53%, respectivamente, e um aumento na rentabilidade de 14,18%, 7,65% e 24,38%, respectivamente. Estas tecnologias incrementam a rentabilidade do sistema de producao de leite com vacas F1 Holandes x Gir. DOI:10.15528/2176-4158/rcpa.v16n2p79-88

EFEITO DO GANHO DE PESO NA RENTABILIDADE DA TERMINAÇÃO EM CONFINAMENTO DE BOVINOS DE CORTE EM CONFINAMENTO

This study aimed to make a simulation of the effect of weight gain for the profitability of finishing beef cattle in feedlot conditions and identifying the most influential components on the final costs of the activity. The analysed data were from the simulation of the finishing of 500 male castrated bovines, with an average daily weight gain of 1,1; 1,3; 1,5 and 1,7 kg. The electronic processing of data was made using an electronic spread - sheet. From the results, it was concluded that effective weight gain significantly affected the profitability of the finishing of beef cattle in feedlot conditions, the weight gain of 1,3 kg, offering greater profitability. The rate of weight gain influenced the onus of the component items in the effective operational cost of the activity, these being different in each of the studied weight gains.